1. Field of the Invention
This invention concerns security door and frame construction and relates primarily to safes but is applicable to security doors.
2. Description of the Prior Art
In our co-pending Australian application for Patent No. 2003252867, we describe security door constructions of the swing and slide type. The door frame has an upright for supporting the door on an offset hinge and the upright of the frame opposite the hinge has a slot capable of receiving the closing edge of the door, which upon closing slides into the slot and upon opening, slides out of the slot.
The slide motion of the door precedes the opening swing and it is this retraction of the door from the slot which intruders try to achieve. The door is free to slide on the hinges and must be retained in the locked position by door bolts. We describe hook and slot formations in the above application which resist prying forces applied to the door. In co-pending Australian application no. 2004231234, we describe a horizontal bar which slides across the width of the door when the safe is locked and abuts the safe wall adjacent the door hinge. Prying forces tending to slide the door open are transmitted to the safe wall and resisted.
In co-pending Australian application no. 2005901184, we describe door mounted rise and fall hooks which drop into vertical slots in the closing stile of the door frame when the door is locked. These are both effective measures for resisting forces exerted by prying bars applied to the door frame, that is between the door and the closing stile.
In safes such as gun safes which are made from plate 2-3 mm thick, the above devices exert locking force at various sites and the metal between these sites could be bent. It would be desirable to resist prying by increasing the difficulty of inserting the prying bar into the gap between the door and the closing stile so that effective leverage cannot be applied.